1.5 [4] <1.6> Consider three different processors P1, P2, and P3 executing

the same instruction set. P1 has a 3 GHz clock rate and a CPI of 1.5. P2 has a

2.5 GHz clock rate and a CPI of 1.0. P3 has a 4.0 GHz clock rate and has a CPI

of 2.2.

a. Which processor has the highest performance expressed in instructions per second?

b. If the processors each execute a program in 10 seconds, fi nd the number of

cycles and the number of instructions.

c. We are trying to reduce the execution time by 30% but this leads to an increase

of 20% in the CPI. What clock rate should we have to get this time reduction?